Does the dipstick tube take an O-ring?

[71CHEVYSHORTBED402]

When I removed the dipstick tube I was surprised to see there wasn't an O-ring. But I ended up finding one when I pulled the oil pan. It was on the rim inside the oil pan tube. It's possible one was added when the engine was rebuilt long ago.

Word is dipstick tubes don't take an O-ring because the tube is press fit and they're not necessary? I asked a transmission shop for an O-ring, and they also say the tube doesn't use one. So my question is, does the original oil dipstick tube use an O-ring or not? Thank you

[towbar]

never seen or used an o-ring on sbc or bbc such as yours....but have used a small dab of sealer on the tube at the time of install to prevent any seepage.

[projectking]

+1 I’ve always put a small amount of black RTV on them.

[jocko]

yep, no-o-ring. It's a press fit, that's all. But RTV not a bad idea for insurance. I don't think the factory used any. But then again, these engines were exactly known for being leak-resistant ...

[70STOVEBOLT]

It is not a press fit on my 402. It fits loosely but it does have a bracket welded on with a bolt hole to mount to the exhaust manifold so it cannot come out. I put a small o-ring on it just because.

[leddzepp]

I tried putting an o-ring on one, was unsuccessful even with the thinnest one I could find.

[68panelman]

No O-ring. I've had the loose complete pull out type too. A light hit with a hammer on the upper area before the seat takes care of that problem.

[davepl]

That picture looks like a Moroso pan or similar, not a stock pan. No o-ring that I know of on the stock setup, but probably on some of the aftermarket...

[57larry]

no O ring but you can use RTV snot

[68panelman]

What engine do you have?
My '70 Blazer has it's original 255hp
350, and the dipstick tube is bossed into the block on head mating surface

[70STOVEBOLT]

Big blocks have the dipstick coming out of the right side of the oil pan.

[68panelman]

Thanks, never owned a BB, still learnin everyday!

[Andy4639]

No O-rings that I have ever seen on the oil stick. Transmissions do though!

[Redneck Rydes]

Every big block I have had did use a o- ring,always put on on and a dab of silicone

[68bowtie]

FWIW my “how to rebuild big block chevy engines” book says there is an o-ring.

[71CHEVYSHORTBED402]

Originally Posted by davepl

That picture looks like a Moroso pan or similar, not a stock pan. No o-ring that I know of on the stock setup, but probably on some of the aftermarket...

It's an original 402 oil pan.

Originally Posted by Redneck Rydes

Every big block I have had did use a o- ring,always put on on and a dab of silicone

Originally Posted by 68bowtie

FWIW my “how to rebuild big block chevy engines” book says there is an o-ring.

I hope you guys are happy man, there was nearly a consensus

Seemed to work with an O-ring, I don't recall a leak. I'll see if I can match it up and/or do as suggested above and seal it.

Edit:

This might be it. Part number 274244.https://www.yearone.com/Product/1964...l-camino/8758n

Per the part's book, 274244 was used on all engines.......Don't shoot the messenger(s), miles may vary I ordered one off Ebay and will advise of fit.

EDIT: I got the 274244 O-ring. Looked right, fit on the tube right, too big for the oil pan tube.

The old one could be just dried up, but I believe it's plastic instead of rubber.

[71CHEVYSHORTBED402]

Originally Posted by 71CHEVYSHORTBED402

It's an original 402 oil pan.





I hope you guys are happy man, there was nearly a consensus

Seemed to work with an O-ring, I don't recall a leak. I'll see if I can match it up and/or do as suggested above and seal it.

Edit:

This might be it. Part number 274244.https://www.yearone.com/Product/1964...l-camino/8758n

Per the part's book, 274244 was used on all engines.......Don't shoot the messenger(s), miles may vary I ordered one off Ebay and will advise of fit.

Well, I got the 274244 O-ring. Looked right, fit on the tube right. Oil or not that tube isn't going in all the way, it just bungles up the O-ring because it's too wide for the oil pan tube.

The old one could be just dried up, but I believe it's plastic instead of rubber.

Well, I got the 274244 O-ring. Looked right, fit on the tube right. Oil or not that tube isn't going in all the way, it just bungles up the O-ring because it's too wide for the oil pan tube.

The old one may just be dried up, but I believe it's plastic instead of rubber.

[AussieinNC]

These are always tight to install when using a new o'ring....

I usually have good luck by rubbing petroleum jelly on the o"ring with it on the tube, then place the tube in a freezer for a few hours...

When installing into the sump, a little more petroleum jelly on the sump boss before installing the tube.

Some folk recommend silicon sealer, but I have never needed it if I use a new ring...

[Grumpy old man]

Run a bead of Permatex #1 around the tube shove it in and forget about it .

[Redneck Rydes]

Originally Posted by Grumpy old man

Run a bead of Permatex #1 around the tube shove it in and forget about it .

X2 put it to bed

[71CHEVYSHORTBED402]

Originally Posted by Grumpy old man

Run a bead of Permatex #1 around the tube shove it in and forget about it .

I hear you, but I wanted to give it one more try, cuz I'm CDO as (*)*^. Here's my report

1. The original 274244 is 0.4375 OD X 0.34375 ID.......It would work too.

2. The NOS 274244 is 0.5078 OD X 0.34375 ID..........That's why the bastard doesn't work. NOS or not, it's the wrong O-ring. Yeah, I'm ignorant enough to have spent $8 on an NOS O-ring. I never bought an O-ring before

3. NAPA sells part number 727-2011. It's 0.4375 OD and 0.3125 ID for 59 cents and it works. The ID is just a pinch more narrow than original, but it's not much a stretch. The tube slides in easily, though I did lube it up a bit.


On a side, NAPA sells 727-2012 for 59 cents as well. It's the same O-ring as the impostor 274244.

Originally Posted by Grumpy old man

I understand . He's building by the book .That's why it's fun talking to him , I have a book . I sit my coffee on it every day . But if you find the last O ring in the pan maybe there's another way to skin that cat ? and as far as it leaking or seeping oil I'd feel better using the Permatex

Wasn't in the pan dang it!.......................What's that tube called on the oil pan? It was resting quietly inside on top of the flange. Did have a split in it....It's old like us. I get your meaning. Be a bummer to fall through and end up in the oil pump.

[my56chevytruck]

Originally Posted by 71CHEVYSHORTBED402

When I removed the dipstick tube I was surprised to see there wasn't an O-ring. But I ended up finding one when I pulled the oil pan. It was on the rim inside the oil pan tube. It's possible one was added when the engine was rebuilt long ago.

Word is dipstick tubes don't take an O-ring because the tube is press fit and they're not necessary? I asked a transmission shop for an O-ring, and they also say the tube doesn't use one. So my question is, does the original oil dipstick tube use an O-ring or not? Thank you

Never saw one on a dipstick, so let me ask, are you sure this tube is correct for your engine? Just wondering.

[71CHEVYSHORTBED402]

Originally Posted by my56chevytruck

Never saw one on a dipstick, so let me ask, are you sure this tube is correct for your engine? Just wondering.

Knowing what I do of the truck it's probably the original tube. An image is below, though the clip is in a box someplace. My 72 has a 402 as well, and both dip stick tubes have the same shape. Where it gets tricky is the book says the tube is 3928901, which comes up showing straight tubes, and the retainers may be fixed? I figure 3928901 was a post factory replacement.

[Redneck Rydes]

Lets stop all the B.S. Big Block Chevys take a O ring, small blocks Do not,End of it!

[demian5]

Now is it a square-cut o-ring or traditional round type?